US firm McKinstry has teamed up with Covington Water District (CWD) to install a new hydropower turbine in the utility district’s water main, with the unit expected to generate roughly 70% of the annual energy consumed by CWD’s administrative facilities, reducing energy and operating costs for the utility district.

The turbine system, custom manufactured by Canyon Hydro, was installed in a new water transmission line that connects CWD to Tacoma Water. The 170ft drop between the Tacoma Water source and CWD’s system causes substantial pressure buildup. Traditionally, a pressure reducing valve (PRV) is used to reduce this pressure, which causes energy to be lost as heat and noise. The new turbine installation will reduce the water pressure while also generating energy. McKinstry implemented the turbine system alongside Canyon Hydro, Gray & Osborne and CWD.

In addition to capturing energy that would have otherwise been lost, the project is also environmentally beneficial by reducing the need to run well pumps to pull water out of the ground. While the turbine runs 24/7, McKinstry will continue to verify the system’s performance and guarantee the energy savings for the term of the performance contract.

“Efficiency and innovation were Covington Water District’s focus for their new pipeline,” said Andrew Williamson, McKinstry’s municipal business manager. “We built a great team that pushed sustainability while understanding the need to be able to advance water flow and net energy metering. We provided the turbine to generate power in place of a conventional pressure reducing valve, taking advantage of the district’s new transmission line that was required to address system resiliency.”

The Washington State Department of Commerce provided a grant to cover 25% of the project’s cost. The energy savings performance contract (ESPC) with McKinstry was executed and administered by the Washington State Department of Enterprise Services (DES) Energy Program. To date, the DES Energy Program has managed more than $1.2 billion in ESPC projects, saving its public-sector clients more than $40 million in annual avoided utility costs.

“This is an excellent example of how energy savings performance contracting can be used to find innovative solutions that deliver renewable energy,” said Doug Kilpatrick, energy engineer for the Washington State Department of Enterprise Services. “The new turbine will bring cost savings to the Covington Water District for years to come.”

“Washington state continually seeks opportunities to implement renewable and efficient energy systems that make use of our natural resources,” added Tony Hanson, managing director of capital programs at the Washington State Department of Commerce. “The Department of Commerce Energy Efficiency and Solar Grants program helps strengthen communities across our state as we move ahead together to a low-carbon economy.”

McKinstry will execute regular follow up inspections to ensure the turbine is meeting operational and energy savings expectations.